Fluidic arming system

ABSTRACT

A fluidic arming system for an aerial bomb having a tethered bob preceding the bomb during descent with the bob carrying a ram air operated electrical generator for producing a voltage during descent and storing it in an electronic circuit carried by the bomb. Lack of air pressure causes the memory circuit within the bomb to release the stored electrical energy and electrically trigger a squib carried thereby.

llnited States atet Campagnuolo et a1.

[ Dec. 10, W74

FLUIDIC ARMING SYSTEM Inventors: Carl J. Campagnuolo, Chevy Chase; Charles F. Peer, Silver Spring; David L. Rawlings, North Bellmore, all of Md.

The United States of America as represented by the Secretary of the Army, Washington, DC.

Filed: Nov. 16, 1967 Appl. No.: 684,602

Assignee:

US. Cl 102/70.2 G, lO2/7.4, 102/81 Int. Cl. F42c 5/00 Field of Search 102/2, 7.4, 70.2, 70.2 G,

References Cited UNITED STATES PATENTS 6/1921 l-ladaway et a1. lO2/70.2 G X Morris i. 102/70.2 G X Heilprin 102/70.2 G

Primary Examiner-Samuel W. Engle Attorney, Agent, or FirmSauI Elbaum 9 Claims, 2 Drawing Figures PATENTED 9E3] 75 FIGZ I3 INVENTORS CARL J. CAMPAGNUOLO, CHARLES F. PEER, DAVID L. RAWL!NGS a ATTORNEYS FLUIDIC ARMING SYSTEM BACKGROUND OF THE INVENTION Aerial bombs, have in the past carried a bob which comprises a streamlined; relatively heavy mass descending ahead of but coupled to the nose of the aerial bomb by a tether line whereby, impact of the bob with the ground causes triggering of a squib in the bomb fuse. The most simple systems merely employ normally open switch contacts which, upon impact, close to trigger the squib. Somewhat more sophisticated systems may employ, a piezoelectric crystal carried by the bob at its nose, which upon bob impact emits a voltage and triggers the squib as a result of the generated voltage.

The problems inherent to the above systems include the following:

1. Upon impact, the bob breaks away from the tether and no voltage from the piezoelectric crystal is delivered to the squib or alternatively in the simpler case, the switch contacts remain open;

2. If the bomb falls on trees or heavy foliage, the switch contacts will not close nor will the piezoelectric crystal be sufficiently compressed to trigger the squib, or

3. If the terrain is soft consisting of snow or mud, the crystal may not emit a voltage again due to lack of compression.

The present invention is therefore directed to an improved fluidic arming system for an aerial bomb or other high speed missile moving through the atmosphere wherein, regardless of the degree of impact, the squib carried by the bomb will be activated.

It is-a further object of this invention to provide an improved fluidic arming system for an aerial bomb having a tethered, leading bob which insures triggering of the bomb fuse squib regardless if the bomb falls on trees, heavy foliage or a soft terrain.

It is a further object of this invention to provide an improved fluidic arming system for an aerial bomb of this type in which the time delay between impact of the streamlined bob and triggering of the bomb fuse may be readily and easily varied without materially affecting system reliability.

Other objects of this invention will be pointedout in the following detailed description and claims and illustrated in the accompanying drawing which discloses, by way of example, the principle of the invention and the best mode which has been contemplated of applying that principle.

In the drawing:

FIG. 1 is an elevational view of an aerial bomb of the tethered bob type which employs the fluidic arming system of the present invention.

FIG. 2 is an electrical schematic diagram of the electhe present invention in a preferred form.

SUMMARY OF THE INVENTION The present invention comprises a fluidic operated electrical generator carried by a streamlined bob tethered to an aerial bomb with the generator responsive to missile movement for producing electrical current. An eiectrical circuit coupling the generator to the normally de-energized fuse firing element within the bomb includes a capacitor coupled to the generator and charged thereby during bob and bomb descent. Circuit means responsive to cessation of generator operation causes the capacitor to be discharged through the fuse firing element. The circuit means includes a silicon controlled rectifier.

DESCRIPTION OF THE- PREFERRED EMBODIMENT The fluidic arming system of the present invention has great applicability to aerial bombs of the type which employ a streamlined bob, moving in front of the bomb itself and attached to the bomb nose by means of a tether rope, or line. The aerial bomb 100 is of conventional configuration and construction and has attached to its nose, a streamlined bob 105 by means of a tether type rope or line 104 which extends therebetween. The streamlined bob 105, which has less air resistance than the aerial bomb 100, maintains itself in front of the bomb during descent with the tether line 104 stretched therebetween. While this combination is not new in itself, the present invention resides in the employment of a fluidically operated, ram air responsive electrical generator 13 which is carried by the bob 105 and the electronic triggering circuit for the bomb fuse which is indicated generally at 103 and is normally carried internally of the aerial bomb 100. These two elements comprise the principal components of the fluidic arming system of the present invention. The tether line 104, in addition to acting as the flexible mechanical connecting means between the bomb proper 100 and the bob 105, carries an appropriate electrical conductor or conductors to couple the elements within an electrical circuit. The bob 105 is provided with an axially extending opening which may be in the form of a tube 102 defined by the dotted lines whereby, during descent of the bob 105 ram air passes through the tube and impinges upon the fluidic generator 13. The fluidic generator is a device that transforms pneumatic energy into electrical power. The fluidic generator is shown a permanent magnet and surrounding the reed is acoil in which an electro-magnetomotive force is induced by the vibrations of the reed in the magnetic field. Thus, in the present system the generator acts as a passive battery which produces an electrical voltage only when trical circuit employed in the fluidic arming system of ment in conjunction with an electrical circuit which stores the energy produced by the generator, during a certain operational period and releases this energy when there is no air' pressure entering the ram tube.

Thus. with respect to FIG. I, it is tobe noted that during descent of the bomb and in particular the bob 105, ram air entering tube 102 generates a voltage output for fluidic generator 13, which output is delivered by means of the tether line 104 to the electrical circuit components within the main aerial bomb 100 for firing the bomb fuse.

In addition to this novel combination of elements to achieve firing of the bomb fuse upon cessation of movement of the bob 105, the present invention is directed to the specific electrical circuit for achieving the same in response to cessation of voltage output of the fluidic generator. Reference to FIG. 2 shows fluidic generator 13 as being coupled by means of line 12 to a common or ground point 11 which may in effect be the metallic casing of bob 105. Line leading from the generator may in effect form a portion of the tether line 104 between bob 105 and the aerial bomb 100. The remaining components of the electronic circuit starting with capacitor 15 and moving upwardly are carried internally of the aerial bomb 100 itself as indicated by the dotted line 103. The circuit comprises parallel lines 16 and 16' which act to couple the alternating current output from generator 13 in conjunction with diodes 26 and 17, respectively, to oppositely charged capacitors 28 and 20. In this respect, in line 16, diode 26 acts in conjunction with ground 29 and the alternating current output of fluidic generator 13, to charge capacitor 28 negatively with respect to ground. Oppositely oriented diode 17 acts in conjunction with lines 16', 19 and 21 and ground connection 22 to charge capacitor positively with respect to ground.

Line 25 acts as a cross connection between capacitors 20 and 28 and this line includes a series resistor 23. In addition, a resistor 18 is positioned between diode 17 and capacitor 20 within line 16'. In order to bleed capacitor 28 in response to cessation of output voltage of fluidic generator 13, there is provided a resistance 30 which is connected between capacitor 28 and ground at 31.

A silicon controlled rectifier 39 is used to gate the major portion of the accumulated charge on capacitor 20 to the bomb fuse squib 34 which is shown as grounded at 36 through line 35. The SCR is connected between the capacitor 20 and the squib 34 by lines 32 and 43, and conventionally includes an anode 40, a gate 41 and a cathode 42. The line 32 is connected to the anode, cathode 42 is connected to the squib through line 43 and gate 41 is connected to line 25 at node 24 which is between the resistance 23 and resistance 30. In addition to these elements, the circuit employs a DC isolation capacitor 15 which is positioned within lead connection line 10 between the fluidic generator 13 in bob 105 and the remaining circuit component within section 103 of the bomb 100.

In operation, during the descent of the bomb 100 and bob 105, the ram air entering tube 102 of the bob causes the diaphragm (not shown) of the fluidic generator 13- to vibrate in the fashion set forth in the referred to application. An alternating current output passes through the tether lead 10 to the circuit components within section 103 of the bomb 100. The alternating current output, acting in conjunction with diode 17, charges the capacitor 20 positively with respect to ground. The same voltage, acting in conjunction with diode 26, charges capacitor 28 negatively with respect to ground. Upon impact of the bob with ground, or alternately, under any circumstance in which ram air ceases to pass through tube 102, the fluidic generator 13 ceases to generate an output voltage. At the instant the generator stops emitting voltage, capacitor 28 rapidly discharges to ground at 31 through the relatively low ohmic resistor 30. Prior to this time, since point 27 is at equal potential to point 24 on line 25, gate 41 is very negative due to the presence of resistance 23 5 within this line. With resistor 30 bleeding the negative charge from capacitor 28 and reducing it to zero, both point 27 and point 24 go from negative to positive. In fact, after capacitor 28 is bled completely, resistor 23 and 30 are series coupled to ground through ground connection 31 across positively charged capacitor 20, thereby changing the potential of gate connection point 24 from negative to some positive value. The combination of resistances 23 and 30 will draw some of the positive charge from capacitor 20 through lines 19 and 25. Gate 41, as it goes positive, triggers the SCR and causes the majority of the charge from capacitor 20 to pass through line 32, the SCR 39, line 43 squib 34 and ground 36. Meanwhile, the DC isolation capacitor 15 prevents any reverse DC current flow to generator 13. Obviously, in the absence of capacitor 15 there exists the possibility of a short circuit through diode 26 and fluidic generator to ground rather than the desired flow wherein capacitor 28 is bled through resistance 30 and ground connection 31.

While the present system has great applicability for aerial bomb arming where the object of the device is to obtain an air burst when the bob hits the ground, the present system may be readily employed in an aerial bomb wherein the fluidic generator is carried directly in the nose of the bomb itself and the bob and tether line are eliminated. The system could be employed as well, in missiles which are fired as projectiles, rather than being dropped from aircraft in gravity fashion. In such a modified system when the bomb or projectile hits the ground no air pressure will enter the generator, carried in the nose of the projectile and the memory circuit will release the stored energy and trigger the squib.

With the present system, during bomb descent, the ram air will cause the generator to produce a voltage and store it in the electronic circuit 103 within the bomb. When the bob 105 hits the ground, no air pressure enters the generator 13 and the memory circuit will release the stored energy and trigger the squib 34. If at impact the bob breaks from the tether, no air pressure enters the generator 13 and the circuit in the bomb functions in the identical fashion. If the bomb falls on heavy foliage and comes to rest, again no air pressure enters the generator 13 and activation of the squib takes place.

While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

l. A fluidic arming system for a missile or the like, comprising: a fluidic operated electrical generator operatively coupled to the missile and responsive to missile movement, an electrical circuit including a normally deenergized electrically operated fuse firing ele- 65 ment, a capacitor coupled to said generator and charged thereby, and means responsive to cessation in generator operation for causing said capacitor to be discharged through said fuse firing element.

2. The system as claimed in claim 1 for use in a missile comprising an aerial bomb, said system further including, means in the form of a streamlined bob for carrying said fluidic operated electrical generator, and a tether line including electrical conducting means for delivering said generated voltage to said electrical circuit within said aerial bomb.

3. The system as claimed in claim 1 wherein said means for allowing said capacitor to be discharged through said fuse firing element comprises a semiconductor device connected in series therebetween.

4. A fluidic arming system comprising a fluidic operated electrical generator carried by a missile, and responsive to missile movement for generating an alternating current voltage, a normally de-energized electrical fuse firing device, a first capacitor coupled to said generator and adapted to receive a positive charge, a second capacitor coupled to said generator and adapted to receive a negative charge, means including a resistor coupling said capacitors, means for draining said second capacitor in response to cessation of generator voltage output, a silicon controlled rectifier operatively connected between said first and second capacitors and said electrical fuse firing device whereby, in response to bleeding of said second capacitor to ground, the positive charge on said first capacitor triggers said silicon controlled rectifier to deliver the major portion of said first capacitor charge to said fuse firing element.

5. The system as claimed in claim 4 including oppositely oriented diodes positioned in series, respectively between said first and second capacitors and said voltage generator to achieve positive and negative charging, respectively of said first and second capacitors.

6. The system as claimed in claim 4 further including a DC isolation capacitor electrically connected between said fluidic generator and said first and second capacitors to prevent the base of said silicon controlled rectifier from dropping to ground voltage in response to generator voltage cessation.

7. The system as claimed in claim 4 further including resistance means ground connected across said second capacitor to achieve time delay between generator voltage cessation and current delivery to said fuse firing element.

8. An electronic arming and firing circuit for an ordnance bomb, comprising:

a. a fluidic operated electrical generator.

b. first and second storage capacitors adapted to be positively and negatively charged, respectively, by the generator,

0. an electrically fired squib for initiating one explosive'train in the bomb,

d. an electrical switching device having an input terminal, an output terminal and a gate terminal,

e. means connecting the input and output terminals of the switching device in series between the first capacitor and the squib,

f. means connecting the gate terminal of the switching device to the second capacitor,

g. first resistive means connected in series between one first and second capacitors, and

h. second resistive means connected between the second capacitor and ground, whereby the generator output charges the first and second capacitors to arm the first and the negative charge on the second capacitor prevents the switching device from being actuated, and wherein the cessation of the generator output enables the second capacitor to rapidly discharge through the second resistive means and the first capacitor to begin discharging through the first and second resistive means, thereby raising the potential on the gate terminal of the switching device to actuate same and discharge the first capacitor through the squib.

9. An electronic arming and firing circuit for an ordnance bomb, comprising:

a. a fluidic operated electrical generator,

b. a storage capacitor adapted to be charged by the generator,

c. an electrically fired squib for initiating one explosive train in the bomb,

d. an electrical switch device having an input terminal, an output terminal and a gate terminal,

e. means connecting the input and output terminals of the switching device in series between the capacitor and the squib, and

f. means coupled to the gate terminal of the switching device for actuating the latter in response to the cessation of the generator output, to thereby discharge the capacitor through the squib. 

1. A fluidic arming system for a missile or the like, comprising: a fluidic operated electrical generator operatively coupled to the missile and responsive to missile movement, an electrical circuit including a normally deenergized electrically operated fuse firing element, a capacitor coupled to said generator and charged thereby, and means responsive to cessation in generator operation for causing said capacitor to be discharged through said fuse firing element.
 2. The system as claimed in claim 1 for use in a missile comprising an aerial bomb, said system further including, means in the form of a streamlined bob for carrying said fluidic operated electrical generator, and a tether line including electrical conducting means for delivering said generated voltage to said electrical circuit within said aerial bomb.
 3. The system as claimed in claim 1 wherein said means for allowing said capacitor to be discharged through said fuse firing element comprises a semi-conductor device connected in series therebetween.
 4. A fluidic arming system comprising a fluidic operated electrical generator carried by a missile, and responsive to missile movement for generating an alternating current voltage, a normally de-energized electrical fuse firing device, a first capacitor coupled to said generator and adapted to receive a positive charge, a second capacitor coupled to said generator and adapted to receive a negative charge, means including a resistor coupling said capacitors, means for draining said second capacitor in response to cessation of generator voltage output, a silicon controlled rectifier operatively connected between said first and second capacitors and said electrical fuse firing device whereby, in response to bleeding of said second capacitor to ground, the positive charge on said first capacitor triggers said silicon controlled rectifier to deliver the major portion of said first capacitor charge to said fuse firing element.
 5. The system as claimed in claim 4 including oppositely oriented diodes positioned in series, respectively between said firsT and second capacitors and said voltage generator to achieve positive and negative charging, respectively of said first and second capacitors.
 6. The system as claimed in claim 4 further including a DC isolation capacitor electrically connected between said fluidic generator and said first and second capacitors to prevent the base of said silicon controlled rectifier from dropping to ground voltage in response to generator voltage cessation.
 7. The system as claimed in claim 4 further including resistance means ground connected across said second capacitor to achieve time delay between generator voltage cessation and current delivery to said fuse firing element.
 8. An electronic arming and firing circuit for an ordnance bomb, comprising: a. a fluidic operated electrical generator, b. first and second storage capacitors adapted to be positively and negatively charged, respectively, by the generator, c. an electrically fired squib for initiating one explosive train in the bomb, d. an electrical switching device having an input terminal, an output terminal and a gate terminal, e. means connecting the input and output terminals of the switching device in series between the first capacitor and the squib, f. means connecting the gate terminal of the switching device to the second capacitor, g. first resistive means connected in series between one first and second capacitors, and h. second resistive means connected between the second capacitor and ground, whereby the generator output charges the first and second capacitors to arm the first and the negative charge on the second capacitor prevents the switching device from being actuated, and wherein the cessation of the generator output enables the second capacitor to rapidly discharge through the second resistive means and the first capacitor to begin discharging through the first and second resistive means, thereby raising the potential on the gate terminal of the switching device to actuate same and discharge the first capacitor through the squib.
 9. An electronic arming and firing circuit for an ordnance bomb, comprising: a. a fluidic operated electrical generator, b. a storage capacitor adapted to be charged by the generator, c. an electrically fired squib for initiating one explosive train in the bomb, d. an electrical switch device having an input terminal, an output terminal and a gate terminal, e. means connecting the input and output terminals of the switching device in series between the capacitor and the squib, and f. means coupled to the gate terminal of the switching device for actuating the latter in response to the cessation of the generator output, to thereby discharge the capacitor through the squib. 